Bill,
> I'm looking to get a new antenna and would appreciate some comments
> on comparing the 3-element SteppIR and the 8-element Cushcraft log
> periodic.
>
> The performance in terms of gain, F/B, bandwidth, SWR, power rating
> and beamwidth are close enough to be a wash, so what about the other
> factors?
I think you're looking at some incorrect claims (2 el SteppIR
perhaps?).
Here are the results of a comparison between the ASL2010 and 3-el
SteppIR in AO. The Cushcraft half elements were offset vertically
by the phasing line spacing to make the model a bit easier but the
change should not effect the results.
The SteppIR 3 element yagi vs. 8 element LP on 18' boom in
free space:
LP SteppIR
Band Gain F/R Gain F/R
20 5.0 9.2 7.4 25
17 4.9 12.3 8.3 25
15 4.8 13.0 8.5 20
12 5.0 14.9 8.8 15
10 5.1 14.5 9.0 11
6 n/a 10.1 20 *
*using fixed (auxiliary) parasitic element.
The Log Periodic is an 8 element design on an 18 foot boom. It
should be comparable to the CushCraft ASL-2010 or the Tennadyne
T-8.
K9LA's work with the T-6 shows about .5 db less gain for the
shorter antenna. Preliminary (unverified) results for a 10
element LPDA model show about .8 dB additional gain and 1-2 dB
improved F/R.
73,
... Joe, W4TV
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|